1. Technical Field
The present invention relates to a film pattern forming method, a device, electro-optical apparatus, and an electronic apparatus.
2. Related Art
A method such as photolithography is widely utilized as a method for forming a predetermined patterned wiring and other elements that are used for an electronic circuit, an integrated circuit or the like. The photolithography requires large-scale equipments such as a vacuum apparatus and an aligner. Moreover, there are problems such as: those equipments requiring complex processes in order to form wirings and other elements that are constituted of predetermined patterns; and the manufacturing cost being high, since the material usage efficiency is approximately several percents, most of the materials unavoidably being disposed.
Compared with the above, a droplet discharge method, or, a so-called inkjet method has been suggested for forming the wirings and other elements that are constituted of the predetermined patterns on a substrate, the droplet discharge method discharging the liquid material from the liquid discharge head in droplets (for example, refer to JP-A-11-274671 and JP-A-2000-216330). In the inkjet method, a liquid material (functional fluid) for patterning is deposited in patterns directly on a substrate, thereafter, a heat treatment or a laser illumination is carried out and thus a desired pattern is formed. This method makes a photolithography unnecessary, significantly simplifying the process, and reduces the usage volume of the raw material since the material is directly deposited on the pattern location.
In recent years, circuits constituting devices are increasingly produced in a high-density, demanding a further miniaturization and thinning of, for instance, wirings. However, in a pattern forming method using the droplet discharge method described above, the discharged droplets spread out on a substrate after the landing, making it difficult to stably form the minute patterns. Especially when the pattern is a conductive film, the spread droplets cause liquid retention pits (bulges), possibly resulting to be a cause of defects such as disconnection and short circuit. Given this factor, a technique which uses a bank structure has been suggested, where the bank structure includes: a wide wiring-formation region; and a minute wiring-formation region that is formed being connected to the wide wiring-formation region (for example, refer to JP-A-2005-12181). In this technique, the functional fluid is discharged onto the wide wiring-formation region, and is made to flow into the minute wiring-formation region resulting from a self-flow of the capillary phenomenon.
The common technique described above, however, involves the following problem.
In order to stably form minute wiring patterns, it is critical to make the length, into which the droplets are flown in, short (i.e., to make the area small), while a certain length is required for fulfilling a prescribed function, and cannot be shortened more than is necessary.